The present invention relates to power tools and, more particularly, to power tools such as power screwdrivers with manual spindle locks.
Varying torque or force is applied to a fastener as the fastener, such as a screw or bolt, is advanced into or removed from an anchoring position. Ordinarily, large forces are required to set the screw during installation or to initially break loose the screw during removal. In small power tools, difficulties are encountered in generating these large forces. The underlying limitation of these tools is the motor horsepower. This problem is further aggravated in battery operated tools. In battery operated tools, to have sufficient electrical capacity from the battery to operate a high torque power tool, a large heavy size tool is required. Thus, lightweight self-contained battery operated tools are limited in the amount of torque which can be produced.
To alleviate the shortcomings, the prior art teaches conventional screwdrivers being utilized with power tools to deliver the high torque. Also, elaborate drive trains may be associated with the power tool to deliver the increased torque. However, this lowers the drive speed. Further, different types of shaft locks have been provided. The shaft locks provide the powered screwdriver with the high torque feature of a manual screwdriver when required. Thus, it is desirable to have a power tool with a manual spindle lock to be utilized in high torque situations.